Finding the Fourth Proportional to 1,284.80, 1,922.34 and 765.08

Step by Step Solution

1. Step 1: Write the proportion equation
   1,284.80 : 1,922.34 = 765.08 : x
2. Step 2: Convert to fraction form
   1,284.80/1,922.34 = 765.08/x
3. Step 3: Cross multiply
   1,284.80x = 1,922.34 × 765.08
4. Step 4: Simplify right side
   1,284.80x = 1,470,743.89
5. Step 5: Solve for x
   x = 1,470,743.89/1,284.80
6. Step 6: Final answer
   x = 1,144.73